It's good to know that only the two parts of the cockpit marked in the picture below are the ones we're going to work with.
The other panels are not important.

First, set switches 1, 2, 3, and 4 as shown in the picture below (switch 1 to the right, switch 2, 3 and 4up) to turn the whole thing on.
The digital display on the right should now read "8888" (blinking).

Next, switch A and Cup and switch B and Ddown (see the picture below).
The digital display should now read "03--".

Lastly, switch A and Cdown and switch B and Dup (see the picture below once again).
The digital display should now read "--28".

So, we've just found out that the radio frequency of the flying wing is 0328!